LDGSL/1107/A/1/3
Lamont Geological Observatory, 1967-1968
Dec 1967-Feb 1968
LDGSL/1107/A/1/4
Princeton University, 1968
Mar-May 1968
LDGSL/1107/A/1/6
Cambridge University, Jan-Mar 1969
Jan-Mar 1969
LDGSL/1107/A/1/13
General scientific correspondence, 1973
1973